Abstract
A good understanding of musculoskeletal pathologies not only requires a good knowledge of normal human anatomy but also an insight in human evolution and development. Biomechanical studies of the musculoskeletal system have greatly improved our understanding of the human musculoskeletal system via medical imaging, modeling and simulation techniques. The same techniques are, however, also used in the study of nonhuman species and a comparison of human and nonhuman data can yield interesting insight in form-function relationships and mechanical constraints on motion.
Anatomical and biomechanical studies on dogs and rabbits have already yielded valuable insight in disease mechanisms and development of musculoskeletal pathologies such as osteoarthritis (OA). Nonhuman primates have, however, rarely been studied in this context, though they may prove particularly valuable as they can provide us with an evolutionary context of modern human anatomy and pathology. The high prevalence of osteoarthritis in modern humans and its rare occurrence in wild primates has previously been explained as due to human joints being ‘underutilized’ or ‘underdesigned’. Modern humans are highly specialized for bipedalism, while nonhuman primates typically use a wide range of locomotor modes and joint postures to travel through the three-dimensionally complex forest canopy. These hypotheses can, however, be challenged, as it seems more likely that the low occurrence of OA in wild primates is due to a combination of underreporting of the disease and absence of the ageing effect in these species. Our understanding of musculoskeletal function and disease in modern humans would clearly benefit from more studies investigating the occurrence and characteristics of OA in nonhuman primates.